We just published a Lab Validation Report for Windows Server 2008 Hyper-V, which was written by Enterprise Strategy Group.  This report goes over the installation and configuration of Windows Server 2008 Hyper-V and management of those servers with Virtual Machine Manager 2008.

More importantly, the report reviews the performance of Windows Server 2008 Hyper-V in comparison with physical systems, so you can compare how applications might run in a virtualized environment.  If you are interested in some Hyper-V performance numbers, download the report.